Header



June 9, 1953 J. E. LOEFFLER 2,641,284

r 4 HEADER Filed 001:. 25, 1946 5 Fig. 2

John E. 1. oeff/er Patented June 9, 1953 HEADER John E. Loeffler, Houston, Tex., assignor to Thornhill-Oraver Company, Houston, Tex., a

corporation of Texas Application October 23, 1946, Serial No. 705,081

7 Claims.

This invention relates to headers or return bend fittings and refers more particularly to the seats and plugs used in conjunction with plug type fittings of this character.

In furnace work of the type utilizing a continuous tubular passage surrounding a heating chamber, return bend fittings are employed to connect the ends of adjacent tubes. It is often desirable to roll the tube ends into the tube receiving openings of the fittings. In order to facilitate the rolling in of the tube ends openings are provided in the header in axial alignment with the tube fittings. These openings also facilitate cleaning or inspection of the interior of the tubes and the removal of damaged tubes. Removable closures are provided to plug up the openings. The closure plugs must provide a seal at all times the furnace is in operation. This has presented a real problem due to the magnitude and variation of both pressure and temperatures that are encountered.

An object of this invention is to provide an improved plug type header capable of operating over wide ranges of temperatures and pressure.

Another object is to provide a plug type header having a seat for a closure plug wherein the seat retains a uniform configuration through wide variations of temperature and pressure conditions and a novel closure plug therefor.

A further object is to provide a plug type header wherein pressure within the header urges a portion of the plug between two inwardly tapered surfaces to insure seating of the plug providing a seal.

Yet another object is to provide an improved closure plug adaptable for use in conjunction with return bend fittings or the like.

Other and further objects of the invention will appear from the following description:

In the accompanying drawings which constitute a part of the instant specification and are to be considered in conjunction therewith, and wherein like reference numerals designate like parts in the various views:

Fig. 1 is an end view of a header embodying this invention wherein one of the closure plugs has been removed for clarity; and

Fig. 2 is an elevational view partially in section of the header shown in Fig. 1.

Referring to the drawings, numeral 3 designates the header body. The body may comprise a casting having two cylindrical fitting portions 4 and an adjoining or supporting bridge portion 5. The fitting portions have openings at each end. The openings 6 are machined to receive a tube, not shown in the drawings, which may be rolled in place. The openings 1 are axially aligned with openings 6 and provide access to the interior of the header to facilitate placement and removal of tube ends in opening 6 and also make possible the cleaning of coke, carbon or other deposits from the interior of the tubes. In addition, the openings provide for inspection of the tube interiors to determine their conditions.

The openings 1 are provided with seats 8. These seats preferably are tapered in order to sealingly receive a closure plug 9. The portion of the body wall which surrounds and supports seat 8 is of uniform thickness. This is accomplished by spacing the seat above the bridge portion 5 of the header. It will be seen by reference to Fig. 2 that the portion of the header which carries the seat is boss like and that the portions of the seat and boss included in any plane passed through the seat normal to the seat axis are of uniform circumferential thickness. Thus, expansion or contraction of the body wall surrounding the seat due to temperature and pressure changes will be uniform and the seat will retain its predetermined configuration,

It is to be understood that any suitable type plug may be used in conjunction with the header of this invention but that the novel plug illus-- trated herein is preferred and provides a simple plug unit which is best adapted for this purpose. The plug comprises the seating portion 9, looking portion Ill and an intermediate or floating portion H. Ihe seating portion has a seating surface adapted to fit seat 8 and an upstanding stem portion l2. It is to be understood that where desired the plug 9 may have attached thereto the customary and conventional stream line guides for directing the fluid entering the header through opening 6 into the passageway through the bridge portion 5 of the header. As these guides are conventional, this has been omitted from the drawings in the interest of simplicity.

An annular member iii constitutes the locking portion of the plug. Member ID has formed thereon radial lugs l3 having inclined upper surfaces I to. These surfaces i3a engage corresponding but oppositely inclined surfaces on internal radial lugs l4 adjacent the opening I of the header to provide a bayonet type locking means. Spaces are provided between lugs it of the plug member l0 and lugs M of the header. These spaces permit mating of lugs 13 and It to facilitate insertion and withdrawal of the plug in open-r ing 1 when the header is to be assembled or dismantled.

Member I carries an apertured arm I and the header has an apertured protrusion or ear I6. Bolt I1 is then provided to rotate member Ill to effect a locking engagement of lugs I3 and I4. This is often referred to as a Unibolt coupling.

Locking member It) does nothave a"direct engagement with seating portion 9 of the plug. Direct engagement between the parts is objectionable as rotation of member Ill affects the angular position of seating element 9 in seat '8 and sometimes results in an-imperfect seal;- The axial thrust for sealing the element 9.

Element I I has a swivel connection :withmember I0. A portion of reduceddiameter of element H extends within the enlarged-bore of member I0. Confronting-grooves are provided in member I0=andelement l I to" receive a split ring I8. The ring- I8 has a loose-fit in the grooves to provide-forrelative rotation between the element and member. The diameter of thegroove in member IO is large-enough to accommodate expansionof ring I8 on assembly of the unit. The floatingelementpreferably has a tapered connection with the seating plug 9.

The tapered connection between plug 9 and floating member II is especially desirable in installations wherein high pressures are likely to be encountered. The angle of inclination of the angular taper of member II differs from that of seat Band is such a's to provide an annular space with taperedsidesu Asimember II is'firmly held against. upward axial displacement by locking member IO, the'portion of plug 9 fitting between thetaperedsurfaces' is wedged inplace. When plug 9 is forced slightly upwardly by pressure-in creases :within the header the seating surface of the plug is held in engagement with surface 8'and the seal therebetween'is'not disturbed. This is accomplished by the tapered surface onthe floating member for it resists displacement of the seating surface of plug 9 from'surface 8.

It is important to note that the lower end of member I 0 engages a shoulder on element I I adjacent. its tapered surface whereby the seating pressure is :not transmitted through ring 'I8. Ring I8 serves only to prevent accidental dis placement 0f the floating element and locking member when disassembled andto facilitate removal of theplug as a'unit' from opening I. .Itisrbelievedthat-the operation'and assembly of theapparatus of this invention isobvious from the foregoing description. The header is-of more or less conventional construction except forthe position-of seat 8 suchthat the seat retains a'predetermined configuration regardless of expansion orcontraction: of the header body and seat due to pressure and temperature changes. This is accomplished by providing the seat on a boss like "portion of the header bo'dyand spaced'above the bridge portion.

The closure plugis a-three part'unit wherein member 9* serves 'as'the-seating element, element I I provides aswivel connection between the seating element and-the locking means I 0 and the member I0 may be locked in place in opening I on rotation. This rotation-engages lugs-I3 and I4- due to the inclination" of i the .engagingportions of these lugs andt-hus rotation of member) affects axial movement of the :locking -means, floating-element andplug element. Thebolt- II, acting through the aperturesofarm --I S and can other unit with which the header is associated,

the plug unit may be readily removed by removing bolt IT and if necessary, tapping arm I5 to rotate member 'IlJ in a counter clockwise direction as floating element II is providedto-t'ran'smi't them! viewednn-liigs 1. The shock or jar is not transmitteddirectly tc -the seating plug 9 so as to score .or injure the seating surfaces of either the plug f placement of the tubes the plug units may be readily replaced.

- Fromnthewforegoing it will beseen that this invention is one well.adapted-to-attain all of the ends and-objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure.

It will be understood that certain features and subcombinations are of utility and may be employed without referenc e to other features and subcombinations. Thisis contemplated by and is within the scope of the claims.

As -many possible embodiments may be made of the invention without departing from the scope thereof it is to be understood that all matter herein set forthorshown in the accompanying drawings is tobe interpreted as illustrative and not in a limiting sense.

Having described my-invention, I claim:

L'In a plug, type-header or return bend fitting, an opening in the headerwall, a seat in the opening for receiving a closure plug, the seat and'surrounding supporting wall having a uniform thickness 'whereby the seat retains a predetermined configuration underapplication of pressure by the plug and regardless'of temperature changes.

2. In a plug type header or return bend fitting including abody withspaced apart fitting portions, a supporting bridge therebetween,-and a passageway establishing -communication' between the portions, an opening in one of the portions and a seat disposed in the opening, said seat andsurroundingbody wall having a uniform thickness. upon all planes passing-through the seat and normal to-the seat axis, whereby the seat retains a predetermined configuration-regardless of temperature variations.

- 3.--In aplug type header-adaptablefor use as a return bend fitting for tubes or the like,including a body having spacedeapart tube receiving portions with a supporting bridge therebetween and a-passa'ge communicating between said portions,-an-openingin one of said portions, and

municating with the continuous passage a seat in the boss spaced from the main portion of the body and adapted to receive a closure plug, said boss being spaced from the supporting bridge so that the boss and bridge do not reside in common planes whereby the boss and wall surrounding the seat may be of uniform thickness on any plane normal to the seat axis and included in the seat.

5. In a high pressure member having an opening and a plug therefor, a seat in the opening with an outwardly tapered seating surface, a removable locking assembly to secure the plug in the opening upon the seat, said locking assembly including an annular member engageable with the plug to urge the plug into sealing engagement with the seat, said annular member having an upwardly directed fiat shoulder, a locking member having its lower end surface complementary to the surface of the flat shoulder of the annular member and engageable with said fiat shoulder of the annular member to urge the same into contact with the plug, and a loose swivel connection between the annular member and locking member permitting rotative and limited lateral movement of the locking member relative to the annular member and plug.

6. In a plug type header or return bend fitting wherein an opening is provided in the header wall, an annular seat within the opening, a closure plug element adapted to engage the seat and having an axial stem extending outwardly through the opening, an annular follower member surrounding the stem and engageable with the upper surface of the plug element, said follower member having an external annular flat shoulder nearer its lower portion, an annular locking member surrounding the upper portion of the follower member and having its lower end surface complementary to the surface of the flat shoulder of the follower member engageable with the flat shoulder of said follower member to urge the same into contact with the plug, and a loose swivel connection between the locking member and the follower member which permits rotative as well as limited lateral movement of the locking member with respect to the follower member.

7. In a plug type header or return bend fitting wherein an opening is provided in the header wall, an annular seat within the opening, a closure plug element adapted to engage the seat and having an axial stem extending outwardly through the opening, an annular follower member surrounding the stem and engageable with the upper surface of the plug element, an annular locking member surrounding the upper portion of the follower member and engageable with said follower member to urge the same into contact with the plug, and a loose swivel connection between the locking member and the follower member which permits rotative as well as limited lateral movement of the locking member with respect to the follower member, the annular seat and surrounding supporting wall having a uniform thickness whereby said seat retains a predetermined configuration under application of pressure by the plug element and regardless of temperature changes.

JOHN E. LOEFFLER.

References Gited in the file of this patent UNITED STATES PATENTS Number Name Date 1,694,595 Howard Dec. 11, 1928 1,710,513 Primrose Apr. 23, 1929 1,753,387 Pierce Apr. 8, 1930 1,767,677 Huff June 24, 1930 2,076,850 Key Apr. 13, 1937 2,266,600 Holtzworth Dec. 16, 1941 2,329,411 Mosher Sept. 14, 1943 2,342,140 Hamilton Feb. 22, 1944 2,352,249 Briggs June 27, 1944 2,370,804 Laurent Mar. 6, 1945 

